This is an issue of perception, not of fact.
The original post is ridiculously long , full of mostly irrelevant information.
There is no way for the original poster to know that the engines flamed out. Upon encounter with turbulence, the pilot retarded the power to reduce speed, the correct response in turbulence.
The airplane did not enter a "nose dive." That may have been the perception, but that does not happen to aircraft, though one may feel a drop; most likely it's a very slight descent, albeit rapid; what one perceives is not necessarily fact.
There's no "backup electrical generator," and were there to be a complete electrical failure, the flight would not have continued to the destination. There is an auxiliary power unit, not run at altitude, and not used to continue to a destination when other options exist.
The landing had nothing to do with the turbulence enroute.